feat(frontend): add API client, layout, and routing

- Create Axios-based API client with sources, jobs, and dashboard endpoints
- Add responsive Layout component with navigation sidebar
- Set up React Router with Dashboard, Backups, and Settings routes
- Configure TanStack Query provider with default options
- Use lucide-react for navigation icons

frontend/node_modules/@tanstack/react-query/build/legacy/suspense.js

@@ -0,0 +1,29 @@
+// src/suspense.ts
+var defaultThrowOnError = (_error, query) => query.state.data === void 0;
+var ensureSuspenseTimers = (defaultedOptions) => {
+  if (defaultedOptions.suspense) {
+    const MIN_SUSPENSE_TIME_MS = 1e3;
+    const clamp = (value) => value === "static" ? value : Math.max(value ?? MIN_SUSPENSE_TIME_MS, MIN_SUSPENSE_TIME_MS);
+    const originalStaleTime = defaultedOptions.staleTime;
+    defaultedOptions.staleTime = typeof originalStaleTime === "function" ? (...args) => clamp(originalStaleTime(...args)) : clamp(originalStaleTime);
+    if (typeof defaultedOptions.gcTime === "number") {
+      defaultedOptions.gcTime = Math.max(
+        defaultedOptions.gcTime,
+        MIN_SUSPENSE_TIME_MS
+      );
+    }
+  }
+};
+var willFetch = (result, isRestoring) => result.isLoading && result.isFetching && !isRestoring;
+var shouldSuspend = (defaultedOptions, result) => (defaultedOptions == null ? void 0 : defaultedOptions.suspense) && result.isPending;
+var fetchOptimistic = (defaultedOptions, observer, errorResetBoundary) => observer.fetchOptimistic(defaultedOptions).catch(() => {
+  errorResetBoundary.clearReset();
+});
+export {
+  defaultThrowOnError,
+  ensureSuspenseTimers,
+  fetchOptimistic,
+  shouldSuspend,
+  willFetch
+};
+//# sourceMappingURL=suspense.js.map